1. Field of the Invention
The present invention relates to a method of manufacturing an image displaying apparatus in which a plurality of electron sources are arranged, and to an apparatus for manufacturing the same.
2. Related Background Art
Conventionally, an electron-emitting device is roughly divided into two known types, i.e., a thermal electron-emitting device and a cold-cathode electron-emitting device. The cold-cathode electron-emitting device includes a field emission type, a metal/insulating layer/metal type, a surface conduction electron-emitting device, and the like.
A surface conduction electron-emitting device is to utilize such a phenomenon that electron emission generates by flowing electric current to a thin film with a small area formed on a substrate, in parallel with the surface of the film. The applicant of the present invention made a large number of proposals on the surface conduction electron-emitting device having a novel structure and its application. The fundamental structure thereof, its manufacturing method, etc. are disclosed in Japanese Patent Application Laid-open Nos. 7-235255, 8-171849, etc., for instance.
The surface conduction electron-emitting device is characterized in that the device has a structure in which a pair of device electrodes facing with each other and a conductive film which is connected to the pair of device electrodes and has an electron-emitting region (fissure) at a part thereof are formed on the substrate. Further, at the end of the fissure, a deposition film is formed which contains as a main component at least one of carbon and a carbon compound.
A plurality of such electron-emitting devices are arranged on a substrate, and the respective electron-emitting devices are connected through wirings, with the result that an electron source having a plurality of the surface conduction electron-emitting devices can be formed. In addition, a display panel of an image displaying apparatus can be formed by combining the electron source and a phosphor.
Conventionally, the manufacture of such electron sources and the display panels are carried out as follows.
As a method of manufacturing an electron source, first, an electron source substrate is formed in which a conductive film, a plurality of devices consisting of a pair of device electrodes connected to the conductive film, and wirings connecting the plurality of devices are formed on a substrate. Then, the manufactured electron source substrate as a whole is disposed in a vacuum chamber, and the exhaustion within the vacuum chamber is performed. Thereafter, a voltage is applied to the respective devices through an external terminal, to thereby cause fissures in the conductive films of the respective devices. In addition, a gas containing an organic substance is introduced into the vacuum chamber, and then a voltage is applied to the respective devices again through the external terminal under the organic substance existing atmosphere, to thereby cause a deposition of carbon or a carbon compound in the vicinity of the fissures.
Further, as a second manufacturing method, first, an electron source substrate is formed in which a conductive film, a plurality of devices consisting of a pair of device electrodes connected to the conductive film, and wirings connecting the plurality of devices are formed on a substrate. The electron source substrate thus manufactured and a phosphor substrate on which phosphors are arranged are joined next while sandwiching a support frame to form a panel of an image displaying apparatus. Thereafter, an exhaustion within the panel is carried out through an exhaust pipe of the panel, and fissures are formed in the conductive films of the respective devices by applying a voltage to the respective devices through an external terminal. In addition, a gas containing an organic substance is introduced into the panel through the exhaust pipe, and a voltage is applied again to the respective devices under the organic substance existing atmosphere, to thereby cause a deposition of carbon or a carbon compound in the vicinity of the fissures.
For manufacturing a vacuum container for a display panel, in which an electron source substrate on which such electron-emitting devices are arranged in matrix and a phosphor substrate provided with phosphors are defined as insides in the respective surfaces, and the inside thereof is made into a high vacuum state, the following process is carried out in which the electron source substrate (hereinafter, also referred to as “RP”) and the phosphor substrate (hereinafter, also referred to “FP”) are disposed oppositely, the inside thereof is sealed using a low-melting point material such as a frit glass and indium as a sealing material, and a vacuum exhaust pipe provided in advance is sealed off after vacuum exhausting the inside from the vacuum exhaust pipe, to thereby form the display panel.
The manufacturing method according to the conventional art described above requires considerably long time for manufacturing one display panel, thus is not suitable for manufacturing a display panel inside of which requires the vacuum degree of 10−6 Pa or more.
The drawbacks of this conventional art were solved by a method described, for example, in Japanese Patent Application Laid-open No. 11-135018.
The above-mentioned methods are used to manufacture the image displaying apparatus, in the first manufacturing method, particularly, as the electron source substrate becomes larger in sizes, the larger-scale vacuum chamber and the exhausting apparatus that can deal with high vacuum are become necessary. Also, the second manufacturing method includes a problem in that it takes a long period of time for exhausting a gas from the space within the panels of the image displaying apparatus, and for introducing a gas containing an organic substance into the space with the panel.
Besides, in the method described in Japanese Patent Application Laid-open No. 11-135018, only a step of sealing two substrates after an alignment (registration) of an FP and an RP is performed in a single vacuum chamber, is used. Therefore, the other processes such as a baking process, a gettering process, and an electron beam cleaning process, which are necessary for the production of the display panel also need to be applied in the single vacuum chamber, respectively. In addition, since movement between each vacuum chamber of the FP and the RP is performed with breaking the atmosphere, each vacuum chamber is vacuum exhausted every time an FP and an RP are carried in. As a result, the manufacturing process time becomes longer. Therefore, considerable reduction of the manufacturing process time has been required, and at the same time, it has been required to attain in a short time a high vacuum degree of 10−6 Pa or more in a display panel during a final manufacturing process.